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How can we change feeble sound to loud sound?

Answer

Loudness of sound is directly proportional to its amplitude.

Feeble sound can be changed to loud sound by increasing its amplitude.

 

What is Supersonic Speed

Answer

When speed of an object is more than speed of sound,it is said to be travelling at supersonic speed

Example

Bullets, Jet Aircraft travel at supersonic speed

  1. Class 9
  2. Chapter 12 Class 9 - Sound (Deleted)

About the Author

CA Maninder Singh's photo - Founder at Teachoo
CA Maninder Singh
CA Maninder Singh is a Chartered Accountant for the past 11 years and a teacher from the past 11 years. He teaches Science, Accounts and English at Teachoo